The 2004 Indian Ocean tsunami struck Phuket's west coast directly, and awareness of that history shapes some of the island's current safety infrastructure — worth understanding without being alarmist about current risk.
What's in place since 2004
A tsunami warning system covers Thailand's Andaman coast, including sirens and evacuation route signage visible along many west-coast beaches, part of a broader regional early-warning system developed after 2004.
Evacuation route signage
Blue signs marking tsunami evacuation routes are visible along beach roads in tourist areas — worth noting their general direction when you arrive at a beach, the same low-effort awareness worth having at any coastal destination.
If a warning siren sounds
Follow posted evacuation routes inland and to higher ground immediately, rather than waiting to confirm the threat — evacuation signage exists specifically so this decision doesn't require additional information in the moment.
Putting current risk in context
A 2004-scale event is a rare occurrence, and daily life and tourism across Phuket's coast have operated normally for two decades since — this is background awareness worth having, not a reason for ongoing concern during a normal visit.